Top: Biogas conditioning unit at the Joint Water Pollution Control Plant operated by the LA County Sanitation Districts. Photo courtesy of LACSD

The Los Angeles County (CA) Sanitation Districts, which manages wastewater and solid waste for over half the residents in Los Angeles County, announced that its operations result in a net reduction of greenhouse gases (GHGs) into the environment. A third party reviewed and verified the Districts’ 2021 emissions inventory. “Our mission is to convert waste into resources,” stated Robert C. Ferrante, the Sanitation Districts’ Chief Engineer and General Manager. “For decades, we and our partners have undertaken activities that reduce GHGs. For example, by converting sewage into recycled water, we reduce the need to import water, the energy used to import water and the GHG emissions used to create energy. We have exceeded carbon neutrality in 2021 and are looking for more ways to reduce regional GHG emissions.”

The combined GHG emissions reduction of 362,000 metric tons of carbon dioxide equivalents (MTCO₂e) was a result of the following programs: biogas-to-electricity, alternative fuels, commodities recycling, water recycling, biosolids land application and composting, and food and green waste diversion, according to the Sanitation Districts’ report, “Reducing Our Carbon Footprint: The Sanitation Districts’ Greenhouse Gas Reduction Initiatives.” The biggest reductions come from the generation of green power. For example, biogas created at the agency’s landfills and wastewater treatment plants is converted into electricity, avoiding production of 190,000 MTCO₂e of GHGs. Renewable natural gas (RNG) is generated from food waste that is preprocessed at the Districts’ Puente Hills Materials Recovery Facility and brought to its Joint Water Pollution Control Plant in Carson for codigestion. The biogas is conditioned into RNG, which is dispensed at the Sanitation Districts’ nearby fueling station that is open to the public. About 78,000 tons of food waste were recycled in 2021, avoiding approximately 42,000 MTCO₂e of GHG emissions.